Hurricane Milton was expected to enlarge even as its intensity ebbed on Tuesday as the now-Category 4 storm grinded past Mexico's Yucatan Peninsula en route to Florida's Gulf Coast, where more than 1 million people were ordered to evacuate before the monster storm arrived

The densely populated west coast of Florida, still reeling from the devastating Hurricane Helene less than two weeks ago, braced for landfall on Wednesday.

The US National Hurricane Center said the storm was likely to hit near the Tampa Bay metropolitan area, where some of the 3 million residents rushed to dispose of mounds of debris left behind by Helene before heeding the evacuation orders. If the hurricane drives directly across the city, it will mark the first time since 1921 that this has occurred.

President Joe Biden on Tuesday urged those who have been ordered to leave before Milton makes landfall in Florida to "evacuate now", saying it was a matter of life and death.

"This could be the worst storm to hit Florida in over a century, and God-willing it won't be, but it's looking like that right now," Biden said.